The effect of various concentrations of 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) on the solubility of dihydroartemisinin (DHA) in aqueous solution at different pHs was investigated. The influence of different co...The effect of various concentrations of 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) on the solubility of dihydroartemisinin (DHA) in aqueous solution at different pHs was investigated. The influence of different concentrations of 2-hydroxypropyl-β- eyclodextrin on the stability of dihydroartemisinin at 50, 60, 70 and 80 ℃ was also studied. Inclusion complex of dihydroartemisinin with 2-hydroxypropyl-β-cyclodextrin was prepared and characterized by X-ray diffraction and differential scanning calorimetry. The 2-hydroxypropyl-β-cyclodextrin effectively inhibited the hydrolysis of dihydroartemisinin and greatly increased its solubility. Furthermore, we showed that the higher concentrations of 2-hydroxypropyl-β-cyclodextrin, the better stability and solubility of dihydroartemisinin. When the temperature was increased, the stability of dihydroartemisinin decreased. Our results indicated that 2-hydroxypropyl-β-cyclodextrin can be used as a stabilizer and solubilizer of dihydroartemisinin.展开更多
In our previous study,a novel organic selenium compound Eb was synthesized and found to have significant antitumor activity with much less toxicity compared with the leading compound Ebselen.Unfortunately,Eb was pract...In our previous study,a novel organic selenium compound Eb was synthesized and found to have significant antitumor activity with much less toxicity compared with the leading compound Ebselen.Unfortunately,Eb was practically insoluble in water (2.57 μg/mL) and had very low oral bioavailability,thus its clinical application was greatly limited.In the present study,the inclusion complex of Eb with 2-hydroxypropyl-β-cyclodextrin (HP-βCD) was prepared and pharmacokinetics of Eb and the inclusion complex were investigated.The water solubility of Eb was dramatically enhanced by inclusion with HP-βCD,which reached 8.4 mg/mL.The pharmacokinetic study showed that the elimination half-life (t 1/2β) of Eb was between 22 h and 30 h and the distribution half-life (t 1/2α) of Eb was 1 h.The results indicated that Eb was rapidly distributed to tissues but slowly eliminated in rats.The absolute bioavailability of Eb/HP-βCD inclusion complex solution through the oral route was 28.3%,and it was 1552% that of Eb in its pure form.In summary,the absorption of Eb in the Eb/HP-βCD inclusion complex was better and faster than that of Eb in its pure form.展开更多
The goal of this study was to improve the solubility and oral bioavailability of tamibarotene by complexing it with hydroxypropyl-β-cyclodextrin(HP-β-CD).The inclusion complex of tamibarotene with hydroxypropyl-β-c...The goal of this study was to improve the solubility and oral bioavailability of tamibarotene by complexing it with hydroxypropyl-β-cyclodextrin(HP-β-CD).The inclusion complex of tamibarotene with hydroxypropyl-β-cyclodextrin(Am80-HP-β-CD)was prepared through a freeze-drying method at the mole ratio of 1:1(Am80:HP-β-CD).Fourier transform infrared spectroscopy(FT-IR)and differential scanning calorimetry(DSC)indicated the formation of Am80-HP-β-CD.In vitro dissolution studies showed that the solubility and dissolution percentage of Am80-HP-β-CD was improved substantially compared to Am80.An improved dissolution with approximately 97%drug release in 3 min was observed,in comparison with Am80 with approximately 60% release in 45 min.In vivo studies indicated that the AUC0-∞ has increased 2.79 times and the Cmax 4.37 times after the formation of inclusion complex.The decrease of tmaxindicated the Am80-HP-β-CD inclusion complex can be absorbed into blood faster.In short,the solubility and bio-availability of Am80 has notably increased with the complexation of HP-β-CD.Therefore,using the inclusion technique is a promising method to improve the solubility of insoluble drugs.展开更多
In order to set up a simple and effective method for resolution of optical isomers, hydroxypropyl-β-cyclodextrin was bonded to silica-gel, which can be used for preparation of thin-layer chromatography plates. Resolu...In order to set up a simple and effective method for resolution of optical isomers, hydroxypropyl-β-cyclodextrin was bonded to silica-gel, which can be used for preparation of thin-layer chromatography plates. Resolution of clenbuterol and propranolol were investigated on these thin-layer chromatography plates using different combinations of solvent systems at ambient temperature. The best simultaneous resolution was achieved in solvent system of acetonitrilen-butanol (50:50, v/v). Rst values of resolution of clenbuterol hydrochloride and propranolol hydrochloride are 3.6 and 4.3, respectively. The spots of different enantiomers are separated clearly. The results showed that hydroxypropyl-β-cyclodextrin bonded silica-gel could be successful in resolution of chiral adrenergic drugs. The study offers a direct, rapid and reliable method for separation of this kind of optically active compounds.展开更多
Novel insulin-loaded nanoparticles based on hydroxypropyl-β-cyclodextrin modified carboxymethyl chitosan(CMC-HP-β-CD) were prepared to improve the oral bioavailability of insulin. The CMC-HP-β-CD was characterize...Novel insulin-loaded nanoparticles based on hydroxypropyl-β-cyclodextrin modified carboxymethyl chitosan(CMC-HP-β-CD) were prepared to improve the oral bioavailability of insulin. The CMC-HP-β-CD was characterized by FT-IR spectroscopy and 1H-NMR spectra. The insulin-loaded nanoparticles were prepared through crosslinking with calcium ions, and the morphology and size of the prepared nanoparticles were characterized by transmission electron microscopy(TEM) and dynamic light scattering(DLS). Cumulative release in vitro study was performed respectively in simulated gastric medium fluid(SGF, p H=1.2), simulated intestinal fluid(SIF, p H=6.8) and simulated colonic fluid(SCF, p H=7.4). The encapsulation efficiency of insulin was up to 87.14 ± 4.32% through high-performance liquid chromatography(HPLC). Statistics indicated that only 15% of the encapsulated insulin was released from the CMC-HP-β-CD nanoparticles in 36 h in SGF, and about 50% of the insulin could be released from the nanoparticles in SIF, whereas more than 80% was released in SCF. In addition, the solution containing insulin nanoparticles could effectively reduce the blood glucose level of diabetic mice. The cytotoxicity test showed that the samples had no cytotoxicity. CMC-HP-β-CD nanoparticles are promising candidates as potential carriers in oral insulin delivery systems.展开更多
Bakuchiol isolated from Psoralea corylifolia is a naturally occurring prenylated phenolic monoterpene with a variety of bioactivities.The aim of this study was to improve the water solubility and thermal stability of ...Bakuchiol isolated from Psoralea corylifolia is a naturally occurring prenylated phenolic monoterpene with a variety of bioactivities.The aim of this study was to improve the water solubility and thermal stability of bakuchiol through complexing it with hydroxypropyl-β-cyclodextrin(HP-β-CD).The bakuchiol/HP-β-CD inclusion complex's behavior and characterization were investigated by ultraviolet-visible(UV-vis)spectroscopy,Fourier transform infrared spectroscopy(FT-IR),thermogravimetric analysis(TGA),X-ray diffraction(XRD),1H nuclear magnetic resonance(NMR),and two-dimensional(2D)NMR.The obtained results indicated the formation of 1∶1 inclusion complex for bakuchiol with HP-β-CD.Water solubility of bakuchiol was significantly improved by complexation with HP-β-CD as demonstrated by phase solubility studies.The encapsulation of bakuchiol was confirmed by UV-vis,FT-IR,and XRD.The thermal stability was effectively enhanced by TGA and derivative thermogravimetry(DTG)analysis.In vitro antioxidant activity showed that bakuchiol/HP-β-CD inclusion complex had a little higher antioxidant ability than free bakuchiol.Moreover,we got the possible inclusion mode for the bakuchiol/HP-β-CD inclusion complex through NMR analysis.These results suggest that the inclusion complex can be a potentially useful approach in the design of novel formulations of bakuchiol for medical applications.展开更多
To overcome the chemical instability of forsythiaside,the forsythiaside-hydroxypropyl-β-cyclodextrin inclusion complex was prepared by triturating. The inclusion complex was found having a varied UV spectrum and melt...To overcome the chemical instability of forsythiaside,the forsythiaside-hydroxypropyl-β-cyclodextrin inclusion complex was prepared by triturating. The inclusion complex was found having a varied UV spectrum and melt temperature point. Inclusion complex has a higher stability to UV light and temperature over forythiaside itself. Pharmacological evidence showed that inclusion complex has little effect on pharmacokinetics by chicken intravenous injection. This study is favorable for developing preparations for forsythiaside and its clinical application.展开更多
Inclusion behavior of oxybutynin (OBN) with hydroxypropyl-β-cyclodextrin (HP-β-CD) was investigated by ultraviolet absorption spectrum and fluorescence spectrum. A reliable determination of the complex stoichiom...Inclusion behavior of oxybutynin (OBN) with hydroxypropyl-β-cyclodextrin (HP-β-CD) was investigated by ultraviolet absorption spectrum and fluorescence spectrum. A reliable determination of the complex stoichiometry was provided by the continuous variation technique. Alcohol was added to further investigate the mechanism of the inclusion behavior. Thermodynamic constants AG, AH and AS for inclusion interaction of OBN and HP-β-CD were determined. The results show that host-vip complex with molar ratio of 1:1 is formed, and inclusion stability constant between OBN and HP-β-CD is 54.9 L/mol determined by ultraviolet spectrum and 11.1 L/mol determined by fluorescence spectrum. OBN has weak binding ability with HP-β-CD in aqueous solution (stability constant 〈102 L/mol) and addition of alcohol leads to a decrease of stability constant, which indicates that the hydrophobic force contributes to the inclusion process. AG, AH and AS are all less than zero, which indicates that the inclusion process is a spontaneous and exothermic process.展开更多
A method of cross-linking multi-walled carbon nanotubes by a nucleophilic substitution of brominated multi-walled carbon nanotubes using hydroxypropyl-β-cyclodextrin anions was studied. The modified multi-walled carb...A method of cross-linking multi-walled carbon nanotubes by a nucleophilic substitution of brominated multi-walled carbon nanotubes using hydroxypropyl-β-cyclodextrin anions was studied. The modified multi-walled carbon nanotube samples were characterized using thermogravimetric analysis, energy-dispersive X-ray spectroscopy, transmission electron microscopy, scanning electron microscopy, Raman spectroscopy and Fourier transform infrared spectroscopy. The hydroxypropyl-β-cyclodextrin modified multi-walled carbon nanotubes were used as a chiral stationary phase additive for thin-layer chromatography to separate clenbuterol enantiomers, and the chiral separation factor was increased.展开更多
Objective To increase the solubility and relieve the mucous irritation of cantharidin (CA) by preparing cantharidin-hydroxypropyl-β-cyclodextrin (CA/HP-β-CD) inclusion complex. Methods The inclusion complex was prep...Objective To increase the solubility and relieve the mucous irritation of cantharidin (CA) by preparing cantharidin-hydroxypropyl-β-cyclodextrin (CA/HP-β-CD) inclusion complex. Methods The inclusion complex was prepared by co-evaporation method and characterized by differential scanning calorimetry (DSC), X-ray diffractometry (XRD), and nuclear magnetic resonance (NMR). Results The disappearance of CA as well as the shift of exothermic peaks shown in DSC results indicated the complexation phenomenon. XRD results showed that the crystalline CA pattern had disappeared, and in NMR results, H-5 shifted from δ 3.731 to 3.695 after complexation and H-2 shifted from δ 3.626 to 3.598, which suggested that part of the drug had entered the HP-β-CD cavity to form an inclusion complex. The solubility increased 10.3 times after complexation and the mucous irritation of CA was relieved remarkably. Conclusion Through complexation with HP-β-CD, the solubility and dissolution rate of CA are improved significantly, and the irritation of musous is relieved.展开更多
The consequence of polycyclic aromatic hydrocarbons(PAHs)in the environment is of great concern.The hydrophobic properties of PAHs significantly impact phase distribution causing limited bioavailability.Enhanced biode...The consequence of polycyclic aromatic hydrocarbons(PAHs)in the environment is of great concern.The hydrophobic properties of PAHs significantly impact phase distribution causing limited bioavailability.Enhanced biodegradation has been extensively carried out by surfactants and the redeployment effect was recognized.However,the quantitative relationship concerning the impact of solids was rarely reported.A batch of biphasic tests were carried out by introducing Mycobacterium vanbaalenii PYR-1 and hydroxypropyl-β-cyclodextrin(HPCD)into a mixture of phenanthrene solution and various glass beads(GB37-63,GB105-125,and GB350-500).The comparative results demonstrated that HPCD had little effect on microbial growth and was not degradable by bacterium.A model was proposed to describe the biodegradation process.The regression results indicated that the partition coefficient kd(1.234,0.726 and 0.448 L·g–1)and the degradation rate k(0 mmol·L^(–1):0.055,0.094,and 0.112;20 mmol·L^(–1):0.126,0.141,and 0.156;40 mmol·L^(–1):0.141,0.156 and 0.184 d^(–1))were positively and negatively correlated with the calculated total surface area(TSA)of solids,respectively.Degradation enhanced in the presence of HPCD,and the enhancing factor f was calculated(20 mmol·L^(–1):15.16,40.01,and 145.5;40 mmol·L^(–1):13.29,37.97,and 138.4),indicating that the impact of solids was significant for the enhancement of biodegradation.展开更多
Domperidone Maleate (DOM), an antiemetic drug, has been used in treatment of adults and children. It has low aqueous solubility and hence low bioavailability. In present study, an attempt has been made to enhance the ...Domperidone Maleate (DOM), an antiemetic drug, has been used in treatment of adults and children. It has low aqueous solubility and hence low bioavailability. In present study, an attempt has been made to enhance the solubility of DOM by inclusion complexation with Hydroxypropyl-β-Cyclodextrin (HP-β-CD) using kneading technique and formulation of fast disintegrating tablets by using Sodium Starch Glycolate as superdisintegrant. Solubility analysis of DOM in different concentrations of HP-β-CD was carried out. Design of experiment (DOE) is done by using MINITAB 15.1 software to find out the variable for dissolution and disintegration time. HP-β-CD and SSG were identified as the variable for disintegration time and dissolution. For optimization of the concentration of HP-β-CD and SSG, two factors at two levels design through central composite design (CCD) were used which gave 13 formulations. All formulations are evaluated for characteristics such as weight variation, hardness, friability, disintegration time and dissolution of drug. Solubility of DOM increases linearly with increase in concentration of HP-β-CD. The optimum concentration of HP-β-CD is found to be in 1:2 molar ratios and SSG of 7%. The In-Vitro dissolution studies of optimized formulation and market sample were carried out in USP type II apparatus at different time intervals of 5, 10, 15 and 30 minutes at 50 rpm in 0.1 N HCl. The dissolution and disintegration time of optimized formulation is found better than market sample.展开更多
Fluvoxamine(FXM)is a well-known selective serotonin reuptake inhibitor(SSRI)for treating depression and has recently been repurposed for efficacious treatment of coronavirus disease 2019.Although cyclodextrin(CD)encap...Fluvoxamine(FXM)is a well-known selective serotonin reuptake inhibitor(SSRI)for treating depression and has recently been repurposed for efficacious treatment of coronavirus disease 2019.Although cyclodextrin(CD)encapsulation effectively improves the physicochemical properties of structurally diverse SSRIs,the molecular understanding of their associations is deficient.This comprehensive study used single-crystal X-ray diffraction integrated with density functional theory(DFT)calculation to provide deep insights into the conformationally flexible FXM and its inclusion complexation withβ-CD.Xray analysis revealed the first crystallographic evidence of the uncomplexed 3FXM-H^(+)·3maleate-(1).Three FXM-H^(+)ions are counter-balanced by three planar maleate-ions to form a thin layer stabilized by infinite fused H-bond rings R_(4)^(4)(12)and R_(6)^(4)(16)and the interplay ofπ…π,CF…πand F…F interactions.For 2β-CD·2FXM-H^(+)·maleate^(2-)·23·2H_(2)O(2),the tail-to-tailβ-CD dimer encapsulates two FXM-H^(+)4-(trifluoromethyl)phenyl moieties,which are charge-balanced by the rare non-planar maleate2and stabilized by N…OH…O H-bonds and F…F interactions.This is a hostevip recognition pattern uniquely observed for allβ-CD complexes with halogen(X)-bearing SSRIs,indicating the essence of X…X interactions and the shielding of X-containing moieties in the wall of theβ-CD dimer.DFT calculations unveiled that the monomeric and dimericβ-CD-FXM complexes and FXM isomers are energetically stable,which alleviates the numbness and bitterness of the orally administered drug as previously patented.Additionally,an insightful conformational analysis of FXM emphasizes the importance of drug structural adaptation in pharmacological functions.展开更多
Nineβ‐cyclodextrin derivatives containing an amino group were synthesized via nucleophilic sub‐stitution from mono(6‐O‐p‐tolylsulfonyl)‐β‐cyclodextrin and used in asymmetric biomimetic Mi‐chael addition re...Nineβ‐cyclodextrin derivatives containing an amino group were synthesized via nucleophilic sub‐stitution from mono(6‐O‐p‐tolylsulfonyl)‐β‐cyclodextrin and used in asymmetric biomimetic Mi‐chael addition reactions in water at room temperature. The mechanism responsible for the moder‐ate activity and enantioselectivity of the β‐cyclodextrin derivatives was explored using nuclear magnetic resonance spectroscopy, namely 2D 1H rotating‐frame overhauser effect spectroscopy (ROESY), ultraviolet absorption spectroscopy, and quantum chemical calculations, which provide a useful technique for investigating the formation of inclusion complexes. The effects of the pH of the reaction medium, theβ‐cyclodextrin derivative dosage, the structure of the modifying amino group, and various substrates on the yield and enantioselectivity were investigated. The results indicated that these factors had an important effect on the enantiomeric excess (ee) in the reaction system. Experiments using a competitor for inclusion complex formation showed that a hydrophobic cavity is necessary for enantioselective Michael addition. A comparison of the reactions using 4‐nitro‐β‐nitrostyrene and 2‐nitro‐β‐nitrostyrene showed that steric hindrance improved the enan‐tioselectivity. This was verified by the optimized geometries obtained from quantum chemical cal‐culations. An ee of 71%was obtained in the asymmetric Michael addition of cyclohexanone and 2‐nitro‐β‐nitrostyrene, using (S)‐2‐aminomethylpyrrolidine‐modified β‐CD as the catalyst, in an aqueous buffer solution, i.e., CH3COONa‐HCl (pH 7.5).展开更多
Cetyltrimethylammonium bromide (CTAB)/potassium bromide (KBr) micellar system has been used as a viscosity probe to study the inclusion complexation between β-cyclodextrin (β-CD) and CTAB. Viscosity measuremen...Cetyltrimethylammonium bromide (CTAB)/potassium bromide (KBr) micellar system has been used as a viscosity probe to study the inclusion complexation between β-cyclodextrin (β-CD) and CTAB. Viscosity measurements show that the inclusion complexation between β-CD and CTAB may cause the breakdown of CTAB/KBr wormlike micelles, resulting in the decrease of the solution viscosity. The viscosity minimum at Cβ-CD/CCTAB=2 indicate the molecular ratio of host molecule to vip molecule is 2:1 in the β-CD/CTAB inclusion complex.展开更多
A small shielding effect on the hydrogen atoms of chiral carbons of β-cyclodextrin (β-CD) was detected by 1H nuclear magnetic resonance, but a large environmental change of the chiral carbon atoms at high concentr...A small shielding effect on the hydrogen atoms of chiral carbons of β-cyclodextrin (β-CD) was detected by 1H nuclear magnetic resonance, but a large environmental change of the chiral carbon atoms at high concentration ratios of lithium carbonate (Li2CO3) to β-CD was observed by polarimetry in aqueous solution. These findings urged us to investigate whether different formation conditions of the molecule-ion system between Li2CO3 and β-CD in solid state were involved in different spectral performances. To answer the question, we prepared three adducts of Li2CO3 to β-CD, i.e., samples 1, 2, and 3, by magnetic stirring, solvothermal and grinding conditions, respectively. Powder X-ray diffraction and Fourier transformation infrared spectroscopy provided the information of formation of the three molecule-ion adducts. Besides, scanning electron microscope images provided different surface information of the three adducts. Further, significant spectral differences in thermal behavior of these adducts were found by thermogravimetry and derivative thermogravimetry.展开更多
A facile, efficient and substrate-selective oxidation of aldehydes to carboxylic acids with NaClO catalyzed by β-cyclodextrin in water has been developed. A series of aldehydes which could form inclusion complex with...A facile, efficient and substrate-selective oxidation of aldehydes to carboxylic acids with NaClO catalyzed by β-cyclodextrin in water has been developed. A series of aldehydes which could form inclusion complex with β-cyclodextrin (β-CD) were oxidized selectively with excellent yields.展开更多
Polycyclic aromatic hydrocarbons(PAHs)/heavy metals/fluorine(F) mixed-contaminated sites caused by abandoned metallurgic plants are receiving wide attention. To address the associated environmental problems,this s...Polycyclic aromatic hydrocarbons(PAHs)/heavy metals/fluorine(F) mixed-contaminated sites caused by abandoned metallurgic plants are receiving wide attention. To address the associated environmental problems,this study was initiated to investigate the feasibility of using carboxymethyl-β-cyclodextrin(CMCD) and carboxymethyl chitosan(CMC) solution to enhance ex situ soil washing for extracting mixed contaminants. Further,Tenax extraction method was combined with a first-three-compartment model to evaluate the environmental risk of residual PAHs in washed soil. In addition,the redistribution of heavy metals/F after decontamination was also estimated using a sequential extraction procedure. Three successive washing cycles using50 g/L CMCD and 5 g/L CMC solution were effective to remove 94.3% of total PAHs,93.2% of Pb,85.8% of Cd,93.4% of Cr,83.2% of Ni and 97.3% of F simultaneously. After the 3rd washing,the residual PAHs mainly existed as very slowly desorbing fractions,which were in the form of well-aged,well-sequestered compounds; while the remaining Pb,Cd,Cr,Ni and F mainly existed as Fe–Mn oxide and residual fractions,which were always present in stable mineral forms or bound to non-labile soil fractions. Therefore,this combined cleanup strategy proved to be effective and environmentally friendly.展开更多
In this work,in order to obtain deep clean gas oil,a novel organic–inorganic hybrid(n-C4H9)4N)7H5Si2W18Cd4O68@β-cyclodextrin(abbreviated as TBA-Si WCd@β-CD)composite was synthesized by supporting quaternary ammoniu...In this work,in order to obtain deep clean gas oil,a novel organic–inorganic hybrid(n-C4H9)4N)7H5Si2W18Cd4O68@β-cyclodextrin(abbreviated as TBA-Si WCd@β-CD)composite was synthesized by supporting quaternary ammonium salt of sandwich-type polysilicotungstate onβ-cyclodextrin(TBA-SiWCd@β-CD)as an efficient catalyst for oxidative desulfurization(ODS)of gas oil.The successful composition of the materials explained by the formation of host–vip inclusion complex,which confirmed through FTIR,UV–vis,XRD,SEM,and EDX characterization analyses.Experimental results revealed that the levels of sulfur content and mercaptan compounds of gas oil lowered with 97%removal efficiency.Compared with the ODS treatment of gas oil,the TBA-Si WCd@β-CD composite showed an outstanding catalytic performance for the oxidation of dibenzothiophene(DBT)in the prepared model fuel.The main factors that influence the desulfurization efficiency and the kinetic study of the ODS process were investigated.The prepared heterogeneous catalyst was found to give remarkable reusability for five runs without a discernible decrease in its activity.This study suggested the potential application of the TBA-Si WCd@β-CD catalyst for removal of hazardous sulfur compounds from gas oil fuel.展开更多
The inclusion-complex of CD-MCP (β-cyclodextrin (β-CD) including 1-methylcyclopropene (1-MCP)) was prepared and characterized. Basing on programmed-heating procedure and weight-temperature analysis, as well as...The inclusion-complex of CD-MCP (β-cyclodextrin (β-CD) including 1-methylcyclopropene (1-MCP)) was prepared and characterized. Basing on programmed-heating procedure and weight-temperature analysis, as well as the application of Satava-Sestak's, Ozawa's and Kissinger's methods, the mechanism and kinetics of thermal dissociation of this inclusion complex were studied. An additional mass loss is found at 170-180℃. The mechanism of thermal dissociation of CD-MCP is dominated by a one-dimensional random nucleation and subsequent growth process (A2/3). The activation energy Es and the pre-exponential factor AS for the process are 102.14 kJ/mol and 3.63×10^10s^-1, respectively. This ES value shows that there is no strong chemical intere, ctions between β-CD and 1-MC;P,展开更多
文摘The effect of various concentrations of 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) on the solubility of dihydroartemisinin (DHA) in aqueous solution at different pHs was investigated. The influence of different concentrations of 2-hydroxypropyl-β- eyclodextrin on the stability of dihydroartemisinin at 50, 60, 70 and 80 ℃ was also studied. Inclusion complex of dihydroartemisinin with 2-hydroxypropyl-β-cyclodextrin was prepared and characterized by X-ray diffraction and differential scanning calorimetry. The 2-hydroxypropyl-β-cyclodextrin effectively inhibited the hydrolysis of dihydroartemisinin and greatly increased its solubility. Furthermore, we showed that the higher concentrations of 2-hydroxypropyl-β-cyclodextrin, the better stability and solubility of dihydroartemisinin. When the temperature was increased, the stability of dihydroartemisinin decreased. Our results indicated that 2-hydroxypropyl-β-cyclodextrin can be used as a stabilizer and solubilizer of dihydroartemisinin.
基金Natural Science Foundation of Beijing (Grant No. 7021001)the Foundation for the Special Program of the Following Novel Candidate Drug by Beijing S&T Committee (Grant No. H20220060190)National Natural Science Foundation (Grant No.30472036)
文摘In our previous study,a novel organic selenium compound Eb was synthesized and found to have significant antitumor activity with much less toxicity compared with the leading compound Ebselen.Unfortunately,Eb was practically insoluble in water (2.57 μg/mL) and had very low oral bioavailability,thus its clinical application was greatly limited.In the present study,the inclusion complex of Eb with 2-hydroxypropyl-β-cyclodextrin (HP-βCD) was prepared and pharmacokinetics of Eb and the inclusion complex were investigated.The water solubility of Eb was dramatically enhanced by inclusion with HP-βCD,which reached 8.4 mg/mL.The pharmacokinetic study showed that the elimination half-life (t 1/2β) of Eb was between 22 h and 30 h and the distribution half-life (t 1/2α) of Eb was 1 h.The results indicated that Eb was rapidly distributed to tissues but slowly eliminated in rats.The absolute bioavailability of Eb/HP-βCD inclusion complex solution through the oral route was 28.3%,and it was 1552% that of Eb in its pure form.In summary,the absorption of Eb in the Eb/HP-βCD inclusion complex was better and faster than that of Eb in its pure form.
文摘The goal of this study was to improve the solubility and oral bioavailability of tamibarotene by complexing it with hydroxypropyl-β-cyclodextrin(HP-β-CD).The inclusion complex of tamibarotene with hydroxypropyl-β-cyclodextrin(Am80-HP-β-CD)was prepared through a freeze-drying method at the mole ratio of 1:1(Am80:HP-β-CD).Fourier transform infrared spectroscopy(FT-IR)and differential scanning calorimetry(DSC)indicated the formation of Am80-HP-β-CD.In vitro dissolution studies showed that the solubility and dissolution percentage of Am80-HP-β-CD was improved substantially compared to Am80.An improved dissolution with approximately 97%drug release in 3 min was observed,in comparison with Am80 with approximately 60% release in 45 min.In vivo studies indicated that the AUC0-∞ has increased 2.79 times and the Cmax 4.37 times after the formation of inclusion complex.The decrease of tmaxindicated the Am80-HP-β-CD inclusion complex can be absorbed into blood faster.In short,the solubility and bio-availability of Am80 has notably increased with the complexation of HP-β-CD.Therefore,using the inclusion technique is a promising method to improve the solubility of insoluble drugs.
基金the National Natural Science Foundation of China(No.20376085,No.20576142)for its financial support.
文摘In order to set up a simple and effective method for resolution of optical isomers, hydroxypropyl-β-cyclodextrin was bonded to silica-gel, which can be used for preparation of thin-layer chromatography plates. Resolution of clenbuterol and propranolol were investigated on these thin-layer chromatography plates using different combinations of solvent systems at ambient temperature. The best simultaneous resolution was achieved in solvent system of acetonitrilen-butanol (50:50, v/v). Rst values of resolution of clenbuterol hydrochloride and propranolol hydrochloride are 3.6 and 4.3, respectively. The spots of different enantiomers are separated clearly. The results showed that hydroxypropyl-β-cyclodextrin bonded silica-gel could be successful in resolution of chiral adrenergic drugs. The study offers a direct, rapid and reliable method for separation of this kind of optically active compounds.
基金Funded by the National Nature Science Foundation of China(No.51273156)the Open Foundation of Hubei key laboratory of Purification and Application of Plant Anti-cancer Active Ingredients(No.HLPAI2014005)
文摘Novel insulin-loaded nanoparticles based on hydroxypropyl-β-cyclodextrin modified carboxymethyl chitosan(CMC-HP-β-CD) were prepared to improve the oral bioavailability of insulin. The CMC-HP-β-CD was characterized by FT-IR spectroscopy and 1H-NMR spectra. The insulin-loaded nanoparticles were prepared through crosslinking with calcium ions, and the morphology and size of the prepared nanoparticles were characterized by transmission electron microscopy(TEM) and dynamic light scattering(DLS). Cumulative release in vitro study was performed respectively in simulated gastric medium fluid(SGF, p H=1.2), simulated intestinal fluid(SIF, p H=6.8) and simulated colonic fluid(SCF, p H=7.4). The encapsulation efficiency of insulin was up to 87.14 ± 4.32% through high-performance liquid chromatography(HPLC). Statistics indicated that only 15% of the encapsulated insulin was released from the CMC-HP-β-CD nanoparticles in 36 h in SGF, and about 50% of the insulin could be released from the nanoparticles in SIF, whereas more than 80% was released in SCF. In addition, the solution containing insulin nanoparticles could effectively reduce the blood glucose level of diabetic mice. The cytotoxicity test showed that the samples had no cytotoxicity. CMC-HP-β-CD nanoparticles are promising candidates as potential carriers in oral insulin delivery systems.
基金Fundamental Research Funds for the Central Universities(No.2232018D3-40)National Natural Science Foundation of China(No.81671508)。
文摘Bakuchiol isolated from Psoralea corylifolia is a naturally occurring prenylated phenolic monoterpene with a variety of bioactivities.The aim of this study was to improve the water solubility and thermal stability of bakuchiol through complexing it with hydroxypropyl-β-cyclodextrin(HP-β-CD).The bakuchiol/HP-β-CD inclusion complex's behavior and characterization were investigated by ultraviolet-visible(UV-vis)spectroscopy,Fourier transform infrared spectroscopy(FT-IR),thermogravimetric analysis(TGA),X-ray diffraction(XRD),1H nuclear magnetic resonance(NMR),and two-dimensional(2D)NMR.The obtained results indicated the formation of 1∶1 inclusion complex for bakuchiol with HP-β-CD.Water solubility of bakuchiol was significantly improved by complexation with HP-β-CD as demonstrated by phase solubility studies.The encapsulation of bakuchiol was confirmed by UV-vis,FT-IR,and XRD.The thermal stability was effectively enhanced by TGA and derivative thermogravimetry(DTG)analysis.In vitro antioxidant activity showed that bakuchiol/HP-β-CD inclusion complex had a little higher antioxidant ability than free bakuchiol.Moreover,we got the possible inclusion mode for the bakuchiol/HP-β-CD inclusion complex through NMR analysis.These results suggest that the inclusion complex can be a potentially useful approach in the design of novel formulations of bakuchiol for medical applications.
基金Supported by National Science&Technology Pillar Program during the TwelfthFive-year Plan Period(2011BAD34B01)National Natural Science Foundation of China(31372485,31172362)the opening fund from Beijing Key Laboratory of TCVM(BUA-TCVM-200904)
文摘To overcome the chemical instability of forsythiaside,the forsythiaside-hydroxypropyl-β-cyclodextrin inclusion complex was prepared by triturating. The inclusion complex was found having a varied UV spectrum and melt temperature point. Inclusion complex has a higher stability to UV light and temperature over forythiaside itself. Pharmacological evidence showed that inclusion complex has little effect on pharmacokinetics by chicken intravenous injection. This study is favorable for developing preparations for forsythiaside and its clinical application.
基金Project(20976041) supported by the National Natural Science Foundation of China
文摘Inclusion behavior of oxybutynin (OBN) with hydroxypropyl-β-cyclodextrin (HP-β-CD) was investigated by ultraviolet absorption spectrum and fluorescence spectrum. A reliable determination of the complex stoichiometry was provided by the continuous variation technique. Alcohol was added to further investigate the mechanism of the inclusion behavior. Thermodynamic constants AG, AH and AS for inclusion interaction of OBN and HP-β-CD were determined. The results show that host-vip complex with molar ratio of 1:1 is formed, and inclusion stability constant between OBN and HP-β-CD is 54.9 L/mol determined by ultraviolet spectrum and 11.1 L/mol determined by fluorescence spectrum. OBN has weak binding ability with HP-β-CD in aqueous solution (stability constant 〈102 L/mol) and addition of alcohol leads to a decrease of stability constant, which indicates that the hydrophobic force contributes to the inclusion process. AG, AH and AS are all less than zero, which indicates that the inclusion process is a spontaneous and exothermic process.
基金Project supported by the National Natural Science Foundation of China (No. 50772133), the Central South University Science Development Foundation (No. 10SDF04), the Planned Science and Technology Project of Hunan Province (No. 2010GK3113) and the Fundamental Research Funds for the Central Universities (No. 201012200146).
文摘A method of cross-linking multi-walled carbon nanotubes by a nucleophilic substitution of brominated multi-walled carbon nanotubes using hydroxypropyl-β-cyclodextrin anions was studied. The modified multi-walled carbon nanotube samples were characterized using thermogravimetric analysis, energy-dispersive X-ray spectroscopy, transmission electron microscopy, scanning electron microscopy, Raman spectroscopy and Fourier transform infrared spectroscopy. The hydroxypropyl-β-cyclodextrin modified multi-walled carbon nanotubes were used as a chiral stationary phase additive for thin-layer chromatography to separate clenbuterol enantiomers, and the chiral separation factor was increased.
基金National S&T Major Special Project on Major New Drug Innovation (2009ZX09301-003&2008ZX09103-390)
文摘Objective To increase the solubility and relieve the mucous irritation of cantharidin (CA) by preparing cantharidin-hydroxypropyl-β-cyclodextrin (CA/HP-β-CD) inclusion complex. Methods The inclusion complex was prepared by co-evaporation method and characterized by differential scanning calorimetry (DSC), X-ray diffractometry (XRD), and nuclear magnetic resonance (NMR). Results The disappearance of CA as well as the shift of exothermic peaks shown in DSC results indicated the complexation phenomenon. XRD results showed that the crystalline CA pattern had disappeared, and in NMR results, H-5 shifted from δ 3.731 to 3.695 after complexation and H-2 shifted from δ 3.626 to 3.598, which suggested that part of the drug had entered the HP-β-CD cavity to form an inclusion complex. The solubility increased 10.3 times after complexation and the mucous irritation of CA was relieved remarkably. Conclusion Through complexation with HP-β-CD, the solubility and dissolution rate of CA are improved significantly, and the irritation of musous is relieved.
文摘The consequence of polycyclic aromatic hydrocarbons(PAHs)in the environment is of great concern.The hydrophobic properties of PAHs significantly impact phase distribution causing limited bioavailability.Enhanced biodegradation has been extensively carried out by surfactants and the redeployment effect was recognized.However,the quantitative relationship concerning the impact of solids was rarely reported.A batch of biphasic tests were carried out by introducing Mycobacterium vanbaalenii PYR-1 and hydroxypropyl-β-cyclodextrin(HPCD)into a mixture of phenanthrene solution and various glass beads(GB37-63,GB105-125,and GB350-500).The comparative results demonstrated that HPCD had little effect on microbial growth and was not degradable by bacterium.A model was proposed to describe the biodegradation process.The regression results indicated that the partition coefficient kd(1.234,0.726 and 0.448 L·g–1)and the degradation rate k(0 mmol·L^(–1):0.055,0.094,and 0.112;20 mmol·L^(–1):0.126,0.141,and 0.156;40 mmol·L^(–1):0.141,0.156 and 0.184 d^(–1))were positively and negatively correlated with the calculated total surface area(TSA)of solids,respectively.Degradation enhanced in the presence of HPCD,and the enhancing factor f was calculated(20 mmol·L^(–1):15.16,40.01,and 145.5;40 mmol·L^(–1):13.29,37.97,and 138.4),indicating that the impact of solids was significant for the enhancement of biodegradation.
文摘Domperidone Maleate (DOM), an antiemetic drug, has been used in treatment of adults and children. It has low aqueous solubility and hence low bioavailability. In present study, an attempt has been made to enhance the solubility of DOM by inclusion complexation with Hydroxypropyl-β-Cyclodextrin (HP-β-CD) using kneading technique and formulation of fast disintegrating tablets by using Sodium Starch Glycolate as superdisintegrant. Solubility analysis of DOM in different concentrations of HP-β-CD was carried out. Design of experiment (DOE) is done by using MINITAB 15.1 software to find out the variable for dissolution and disintegration time. HP-β-CD and SSG were identified as the variable for disintegration time and dissolution. For optimization of the concentration of HP-β-CD and SSG, two factors at two levels design through central composite design (CCD) were used which gave 13 formulations. All formulations are evaluated for characteristics such as weight variation, hardness, friability, disintegration time and dissolution of drug. Solubility of DOM increases linearly with increase in concentration of HP-β-CD. The optimum concentration of HP-β-CD is found to be in 1:2 molar ratios and SSG of 7%. The In-Vitro dissolution studies of optimized formulation and market sample were carried out in USP type II apparatus at different time intervals of 5, 10, 15 and 30 minutes at 50 rpm in 0.1 N HCl. The dissolution and disintegration time of optimized formulation is found better than market sample.
基金supported by the Ratchadapisek Sompoch Endowment Fund,Chulalongkorn University,Thailand(Grant No.:RCU_67_023_010).
文摘Fluvoxamine(FXM)is a well-known selective serotonin reuptake inhibitor(SSRI)for treating depression and has recently been repurposed for efficacious treatment of coronavirus disease 2019.Although cyclodextrin(CD)encapsulation effectively improves the physicochemical properties of structurally diverse SSRIs,the molecular understanding of their associations is deficient.This comprehensive study used single-crystal X-ray diffraction integrated with density functional theory(DFT)calculation to provide deep insights into the conformationally flexible FXM and its inclusion complexation withβ-CD.Xray analysis revealed the first crystallographic evidence of the uncomplexed 3FXM-H^(+)·3maleate-(1).Three FXM-H^(+)ions are counter-balanced by three planar maleate-ions to form a thin layer stabilized by infinite fused H-bond rings R_(4)^(4)(12)and R_(6)^(4)(16)and the interplay ofπ…π,CF…πand F…F interactions.For 2β-CD·2FXM-H^(+)·maleate^(2-)·23·2H_(2)O(2),the tail-to-tailβ-CD dimer encapsulates two FXM-H^(+)4-(trifluoromethyl)phenyl moieties,which are charge-balanced by the rare non-planar maleate2and stabilized by N…OH…O H-bonds and F…F interactions.This is a hostevip recognition pattern uniquely observed for allβ-CD complexes with halogen(X)-bearing SSRIs,indicating the essence of X…X interactions and the shielding of X-containing moieties in the wall of theβ-CD dimer.DFT calculations unveiled that the monomeric and dimericβ-CD-FXM complexes and FXM isomers are energetically stable,which alleviates the numbness and bitterness of the orally administered drug as previously patented.Additionally,an insightful conformational analysis of FXM emphasizes the importance of drug structural adaptation in pharmacological functions.
基金supported by the National Natural Science Foundation of China (21425627,21376279)~~
文摘Nineβ‐cyclodextrin derivatives containing an amino group were synthesized via nucleophilic sub‐stitution from mono(6‐O‐p‐tolylsulfonyl)‐β‐cyclodextrin and used in asymmetric biomimetic Mi‐chael addition reactions in water at room temperature. The mechanism responsible for the moder‐ate activity and enantioselectivity of the β‐cyclodextrin derivatives was explored using nuclear magnetic resonance spectroscopy, namely 2D 1H rotating‐frame overhauser effect spectroscopy (ROESY), ultraviolet absorption spectroscopy, and quantum chemical calculations, which provide a useful technique for investigating the formation of inclusion complexes. The effects of the pH of the reaction medium, theβ‐cyclodextrin derivative dosage, the structure of the modifying amino group, and various substrates on the yield and enantioselectivity were investigated. The results indicated that these factors had an important effect on the enantiomeric excess (ee) in the reaction system. Experiments using a competitor for inclusion complex formation showed that a hydrophobic cavity is necessary for enantioselective Michael addition. A comparison of the reactions using 4‐nitro‐β‐nitrostyrene and 2‐nitro‐β‐nitrostyrene showed that steric hindrance improved the enan‐tioselectivity. This was verified by the optimized geometries obtained from quantum chemical cal‐culations. An ee of 71%was obtained in the asymmetric Michael addition of cyclohexanone and 2‐nitro‐β‐nitrostyrene, using (S)‐2‐aminomethylpyrrolidine‐modified β‐CD as the catalyst, in an aqueous buffer solution, i.e., CH3COONa‐HCl (pH 7.5).
基金This work was supported by the Doctor Research Foundation of Anhui University of Architecture (No.20101201) and the Postdoctoral Science Foundation of Anhui University of Architecture (No.20110101).
文摘Cetyltrimethylammonium bromide (CTAB)/potassium bromide (KBr) micellar system has been used as a viscosity probe to study the inclusion complexation between β-cyclodextrin (β-CD) and CTAB. Viscosity measurements show that the inclusion complexation between β-CD and CTAB may cause the breakdown of CTAB/KBr wormlike micelles, resulting in the decrease of the solution viscosity. The viscosity minimum at Cβ-CD/CCTAB=2 indicate the molecular ratio of host molecule to vip molecule is 2:1 in the β-CD/CTAB inclusion complex.
基金ACKNOWLEDGMENTS This work was supported by the Innovation Foundation of Graduate Students in University of Science and Technology of China (No.KD2008020), and the Natural Science Foundation of Anhui Province (No.090416228).
文摘A small shielding effect on the hydrogen atoms of chiral carbons of β-cyclodextrin (β-CD) was detected by 1H nuclear magnetic resonance, but a large environmental change of the chiral carbon atoms at high concentration ratios of lithium carbonate (Li2CO3) to β-CD was observed by polarimetry in aqueous solution. These findings urged us to investigate whether different formation conditions of the molecule-ion system between Li2CO3 and β-CD in solid state were involved in different spectral performances. To answer the question, we prepared three adducts of Li2CO3 to β-CD, i.e., samples 1, 2, and 3, by magnetic stirring, solvothermal and grinding conditions, respectively. Powder X-ray diffraction and Fourier transformation infrared spectroscopy provided the information of formation of the three molecule-ion adducts. Besides, scanning electron microscope images provided different surface information of the three adducts. Further, significant spectral differences in thermal behavior of these adducts were found by thermogravimetry and derivative thermogravimetry.
基金the National Natural Science Foundation of China(No.20776053)the Program for New Century Excellent Talents in University(No.NCET-06-740)for providing financial support for this project.
文摘A facile, efficient and substrate-selective oxidation of aldehydes to carboxylic acids with NaClO catalyzed by β-cyclodextrin in water has been developed. A series of aldehydes which could form inclusion complex with β-cyclodextrin (β-CD) were oxidized selectively with excellent yields.
基金supported by the National Natural Science Foundation of China (Nos.41030531,41001335G,21377138 and 41271464b)
文摘Polycyclic aromatic hydrocarbons(PAHs)/heavy metals/fluorine(F) mixed-contaminated sites caused by abandoned metallurgic plants are receiving wide attention. To address the associated environmental problems,this study was initiated to investigate the feasibility of using carboxymethyl-β-cyclodextrin(CMCD) and carboxymethyl chitosan(CMC) solution to enhance ex situ soil washing for extracting mixed contaminants. Further,Tenax extraction method was combined with a first-three-compartment model to evaluate the environmental risk of residual PAHs in washed soil. In addition,the redistribution of heavy metals/F after decontamination was also estimated using a sequential extraction procedure. Three successive washing cycles using50 g/L CMCD and 5 g/L CMC solution were effective to remove 94.3% of total PAHs,93.2% of Pb,85.8% of Cd,93.4% of Cr,83.2% of Ni and 97.3% of F simultaneously. After the 3rd washing,the residual PAHs mainly existed as very slowly desorbing fractions,which were in the form of well-aged,well-sequestered compounds; while the remaining Pb,Cd,Cr,Ni and F mainly existed as Fe–Mn oxide and residual fractions,which were always present in stable mineral forms or bound to non-labile soil fractions. Therefore,this combined cleanup strategy proved to be effective and environmentally friendly.
文摘In this work,in order to obtain deep clean gas oil,a novel organic–inorganic hybrid(n-C4H9)4N)7H5Si2W18Cd4O68@β-cyclodextrin(abbreviated as TBA-Si WCd@β-CD)composite was synthesized by supporting quaternary ammonium salt of sandwich-type polysilicotungstate onβ-cyclodextrin(TBA-SiWCd@β-CD)as an efficient catalyst for oxidative desulfurization(ODS)of gas oil.The successful composition of the materials explained by the formation of host–vip inclusion complex,which confirmed through FTIR,UV–vis,XRD,SEM,and EDX characterization analyses.Experimental results revealed that the levels of sulfur content and mercaptan compounds of gas oil lowered with 97%removal efficiency.Compared with the ODS treatment of gas oil,the TBA-Si WCd@β-CD composite showed an outstanding catalytic performance for the oxidation of dibenzothiophene(DBT)in the prepared model fuel.The main factors that influence the desulfurization efficiency and the kinetic study of the ODS process were investigated.The prepared heterogeneous catalyst was found to give remarkable reusability for five runs without a discernible decrease in its activity.This study suggested the potential application of the TBA-Si WCd@β-CD catalyst for removal of hazardous sulfur compounds from gas oil fuel.
文摘The inclusion-complex of CD-MCP (β-cyclodextrin (β-CD) including 1-methylcyclopropene (1-MCP)) was prepared and characterized. Basing on programmed-heating procedure and weight-temperature analysis, as well as the application of Satava-Sestak's, Ozawa's and Kissinger's methods, the mechanism and kinetics of thermal dissociation of this inclusion complex were studied. An additional mass loss is found at 170-180℃. The mechanism of thermal dissociation of CD-MCP is dominated by a one-dimensional random nucleation and subsequent growth process (A2/3). The activation energy Es and the pre-exponential factor AS for the process are 102.14 kJ/mol and 3.63×10^10s^-1, respectively. This ES value shows that there is no strong chemical intere, ctions between β-CD and 1-MC;P,